INVESTIGATION OF THE STRUCTURAL STABILITY OF WELDS IN COLUMBIUM ALLOYS.
Abstract
The second phase of a study of structural stability of welds in typical commercial Nb alloys B66, D43 and Cl29Y is reported. Effects of increased levels of the interstitial elements O and N on postweld aging kinetics and bend transition behavior were determined for welds in these alloys. The effect of yttrium, as an alloy addition, on structural stability of Nb weldments was investigated using W arc and electron beam joining techniques to prepare samples of Cl29Y alloy. Aging studies were conducted in the 1400 to 3000 F temperature range from 1 to 256 hrs. In Cl29Y alloy welds, complex aging phenomena were indicated in the 1400 to 1800F temperature range. In general, increased quantities of the interstitial elements N and O substantially reduced as-welded ductility, but produced only minor effects on post-weld aging kinetics. N additions caused greater reductions in ductility than O in equivalent amts. Heat-treating on non-contaminated welds of the 3 alloys resulted in welds which were ductile at room temperature, even after exposure to re-aging cycles that tended to produce maximum embrittlement without prior overaging treatments. Tests affirmed that delayed cracking can be encountered in hydrogen contaminated D-43 welds.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1966
- Accession Number
- AD0480754
Entities
People
- S. R. Thompson
- W. H. Kearns
- W. R. Young
Organizations
- General Electric